Interesting Water Change Find

[bacffin]

After my tank finished cycling, and after the initial "big" water change, I started doing weekly water changes of 10%. My nitrates were always at 20 to 30ppm and I could not lower them. Even after 4 weeks of 10% changes.

There were no fish in there either, just janitors.
Well, I changed to a 20% water change bi-monthly, added 3 fish and after another 4 weeks, my nitrates are now between 5 and 10ppm and still going down.

Just thought this would be interesting to share. Any comments? h*
Bruce

 

[bacffin]

Anyone know why this is?

 

[birdy]

That is kind of what we are talking about when we say a mature and stable tank.
The LR will reach a point at which it begins processing the nitrates. The water changes help of course, but careful stocking and feeding along with a decent amount of LR should keep Nitrates at an acceptable level.
At some point they may start rising again and you may want to look at a refugium for nitrate export.

 

[tankgirl1]

After my tank finished cycling.....Even after 4 weeks of 10% changes.
How long did you allow the tank to cycle prior to this? I know with my tank after the first 4 or 5 weeks I had an enormous nitrate spike that lasted 2 weeks or more. It gradually came down and has remained within good ranges ever since.
Maybe it just did not cycle long enough or properly to begin with? How did you cycle the tank? Read up on the Nitrogen cycle on this site, or google it. There are lots of variables to tank cycling.
:happyfish

 

[bang guy]

How did you cycle? Did you ever allow Ammonia to climb higher than 0.5ppm during the cycle? How much live rock was in the system during the cycle?

 

[tliss]

I am experiencing a similar problem in my 29 gallon. I do a 20% water change montly as opposed to weekly or bi weekly at this point as the tank contains a few fish and cleanup crew, but no other inverts. The tank has been running since March and I watch the ammonia and nitrite spikes and then added the fish. However, after reading here for a while I went and bought a nitrate test kit and ever since I did that I have not been able to get my nitrates below 40ppm. They have stayed between 40 and 80ppm since I started testing and will not go down, even after water changes. I am contemplating building a fuge for it to take care of this, but in the meantime I'd really like to know what is causing this. I've got roughly 50# of live rock with good coraline growth and 20# of live sand in the sand bed. Thoughts?
Tom

 

[tliss]

Just to follow up...did a 20% water change yesterday.
Nitrate reading before water change - ~80ppm
Nitrate reading today, after the water change - ~80ppm
Time to fuge...
Tom

 

[the reef]

I thought the sam as bang your cycle was being on its way you could have slowed down the cycle by changing the watter two often. Brand new tank setups need to cycle with the watter for about 5 to 6 weeks without watter changes then after the tank is cycled do a 30 to 50 percent water change and if the levels go up again then need more time to cycle. you have gotten results from slowing down your watter changes. This alowed for the tank to cycle.

 

[drew2005]

I had that same issue. It seemed like my nitrates were never going below 20. Then all of a sudden after about a month of weekly 10% changes, i saw 10 then 5 then 0. Ever since then all my parameters have been stable. Ive had 2 clowns in there for over a month and they are happy as can be. I just added a small yellow tang 2 days ago and hes doing great. I know im gonna get alot of crap for puttin a tang in a 46 gallon but i did it anyway. I know plenty of people who have had success with yellows my size tank.

 

[bacffin]

Originally Posted by Bang Guy
How did you cycle? Did you ever allow Ammonia to climb higher than 0.5ppm during the cycle? How much live rock was in the system during the cycle?

I cycled with a cocktail shrimp. I actually had too high of an ammonia spike which went to 7ppm. I cycled it for 8 weeks and 1 week of phantom feeding to be sure I didn't re-spike. I also cycled with 50 lbs. of live rock and 20 lbs. of aragalive sand. Base sand is aragonite ~40 lbs. (45 gallon tank)
I don't think there is a problem here, I just was curious as to why the 10% weekly changes were not as effective as the 20% bi-monthly. I did another test on Sunday (one week after change) and the trates are still between 5 and 10, so this procedure is working for me.
Two weeks ago I added another 10 lbs. of LR from an lfs and it has feather dusters growing on it already, where the original 50 lbs still has no hitch hikers from the "hard" cycle. I read your threads Bang on changing the water when the ammonia reaches 0.5ppm, but that was after I had already let the tank go to high. There are a lot of differing opinions on this subject, but I know how to do it the next time to keep as many hitch hikers as possible.
Thanks,
Bruce

 

[bang guy]

Originally Posted by Bacffin
I cycled with a ######## shrimp. I actually had too high of an ammonia spike which went to 7ppm.
I really dislike the Shrimp method and other "Ammonia Spike" methods but it will work somewhat. You have read my other posts so you already know my theories. I'll go over it briefly just as an fyi for others.
The problem as I see it is allowing Ammonia to climb so high. I would have recommended a lot of water changes to keep the ammonia level low enough for live rock animals to survive.
At 7ppm Ammonia most of the useful animals inside the rock will have perished. It can take months and months for the end product of these decomposing animals to finally be purged from the rock. The result is excessive dissolved nutrients for a long time. These nutrients fuel algae and Cyano blooms and make your rock much less useful.
I know the Shrimp method is really popular now but I hope someone learns from your misfortune.

 

[birdy]

I am not sure I understand what "misfortunes" this person has had with their tank Bang. Sounds perfectly normal to me, most of the tanks I have set up and cycled have a significant level of nitrates for a few months until the tank and LR and water changes get a handle on them and they start to drop. Most people do not want to spend the money for that many water changes so I typically cycle a tank with LR or the feeding method. I totally understand your point and agree with you about doing water changes on a cycling tank and keeping ammonia levels low.
I think Bacffin's main question was why did the nitrates start dropping when he went from weekly 10% changes to bi-monthly 20%, and my thought is it just took the tank maturing and the LR that long to start processing the nitrates, not necessarily the water change method.

 

[bang guy]

Originally Posted by Birdy
I am not sure I understand what "misfortunes" this person has had with their tank Bang.
50 pounds of expensive live rock was reduced to base rock by the 7ppm ammonia spike. That's a significant loss of money. The rock will look the same thankfully but it will not filter the same without the diversity of internal creatures.
You are correct that this is considered normal. It doesn't have to be that way though.
If you're looking at the economics a $40 bucket of salt would have been plenty to save $300+ worth of live rock.

 

[jlem]

Unless your live rock has dried out completely you will have benficial bacteria from the moment that your rock is in your tank. You will have some die off that will overwhelm the existing bacteria at first but the bacteria will quickly multiply to keep ammonia low enough to avoid killing off most of your live rock but high enough to produce plenty of new bacteria. By throwing in shrimp you quickly overkill on the ammonia build up and kill of lots of good stuff that should be able to survive the gradual and mild build up that a natural cycle will produce.

 

[bacffin]

Originally Posted by Birdy
I think Bacffin's main question was why did the nitrates start dropping when he went from weekly 10% changes to bi-monthly 20%, and my thought is it just took the tank maturing and the LR that long to start processing the nitrates, not necessarily the water change method.

That's it exactly, but Bang might be on to something with the slow, long die off process in the live rock. If decomposition does take months, my nitrate issue might be directly related and this will continue. I am by no means experienced, but it does stand to reason because I have not had one critter yet since the end of April when the rock went in. If I do get a critter at some point from deep inside who survived, then I can assume the die off is coming or came to an end.
Now on the other hand, for a mature tank, if my water changes perform better at larger intervals, there might be some other explanation, maybe in terms of a mathematical expression. :thinking:
Bruce

 

[bacffin]

Originally Posted by The reef
I thought the sam as bang your cycle was being on its way you could have slowed down the cycle by changing the watter two often. Brand new tank setups need to cycle with the watter for about 5 to 6 weeks without watter changes then after the tank is cycled do a 30 to 50 percent water change and if the levels go up again then need more time to cycle. you have gotten results from slowing down your watter changes. This alowed for the tank to cycle.

Good point reef, but I shot the ammonia with the shrimp. I was not in a rush to cycle the tank either, I just took the wrong road so to speak. I didn't care how long it took to cycle and if water changes were necessary, then that's what I should have done.
Bruce

 

[jacknjill]

bang, what is your preferred method of cycling a tank?

 

[bang guy]

Originally Posted by JacknJill

bang, what is your preferred method of cycling a tank?

Mix up to 25 gallons of saltwater at a time using filtered water and add to the tank until it's 1/2 full.
Pour in either 1/2" (Shallow bed) or 4" (DSB) of dry aragonite sand and mix it up really good to make sure there are no trapped air bubbles in the sand.
Scoop off the foam on top of the water the next day and start the heater and waterflow. Waterflow should be very turbulent. Don't worry about the sand storm because there's nothing to look at yet anyway.
Add good uncured live base rock. Lay all the rock out on the floor and pull off all visible sponges and anything that looks dead or dying. Do a quick rough estimate of the aquascaping and place the rocks in the general vicinity of where they go. The water will be milky so just make sure the rocks are stable. I like using uncured aquacultured rock because it still has most of its critters alive. Sometimes you can get rock that has been out of the ocean for less than 24 hours. Remove all Mantis Shrimp and Crabs except Porcelain crabs. A seperate species tank can be set up if you want to keep them.
Start up the lights to run 8 hours a day and skimmer running 24/7 once the rock is in the water.
Check the water daily for Ammonia. If Ammonia exceeds 0.5ppm do a 25% water change to try to get it back below 0.5ppm. If Ammonia reaches a really high spike then a 50% change and a dose of AmQuel can be done. The diversity of animals in your live rock is very important to the long term health of your tank. The higher the ammonia level gets the lower the diversity of critters in your live rock.
After several days the sand will begin to settle and you can start working out the final aquascaping. Use a Turkey baster to try to keep as much silt off the rock as you can.
Once Ammonia reaches 0.0ppm I start feeding the tank a very small amount of food. I increase the food dosage a little each day until I'm feeding enough to satisfy a pair of small Clownfish. If Ammonia climbs then feed less or stop feeding. Once Ammonia is at zero I add uncured top rock (the $$ stuff) and stop feeding until the secondary ammonia cycle is finished. Same rules for the top rock as the base rock. Remove dead or dying stuff. This is usually a lot faster. Feed the tank again once Ammonia is back down to zero but don't feed enough to cause Ammonia to accumulate. Then add up to 1/2" of live sand. The more the better but a hand ful will work, just no more than 1/2".
If Ammonia stays at zero for a week or two then I add the Clownfish.
From start to finish this usually takes 4 - 8 weeks.